<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8">
    <title>Title</title>
    
    <style>
      .card {
        border: 1px gray solid;
        border-radius: 10px;
        padding: 15px;
      }
      
      .card-title {
        font-size: 15px;
        font-weight: bold;
        margin: 10px;
      }
      
      .card-body > div {
        color: darkgray;
        background: pink;
        margin: 10px;
        width: 100px;
        height: 100px;
      }
    </style>
  </head>
  <body>
    <!--order属性设置flex项优先级且不影响元素的文档流位置，其属性值越大优先级越低-->
    <div class="card">
      <div class="card-title">`order`属性可以改变flex项布局，而不影响DOM树内该元素的顺序</div>
      <div class="card-body" style="display: flex">
        <div style="order: 1">1</div>
        <div style="order: 0">2</div>
        <div style="order: 0">3</div>
        <div style="order: -1">4</div>
      </div>
    </div>
  </body>
</html>